Transparent conductors are a critical component for touch screen displays and solar cells. The key requirements for a transparent conductor are high transparency, high flexibility, high efficiency and low power consumption. Currently, the most commonly used transparent conductor material is indium tin oxide (ITO). However, ITO is expensive and has limited chemical stability. In addition, ITO is fragile and lacks flexibility.
Graphene is a promising candidate for replacing the ITO in touch screens and solar cells. Graphene is highly transparent (˜97.3%) over wide wavelengths ranging from visible to near infrared (IR). Owing to its covalent carbon-carbon bonding, graphene is also one of the stiffest materials with a remarkably high Young's modulus of ˜1 TPa, yet stretchable and bendable at the same time, with a maximum stretchability of up 20%. However, graphene suffers from high intrinsic sheet resistance (>1 kilo ohms).
Therefore, there remains a need for more cost effective transparent conductors with cheaper fabrication, greater efficiency, and greater flexibility.